V Ramanathan

Near-Term Climate MitigationSide Event, Cop-16

7 December 2010Room Pitaya, Cancun Messe, Mexico

Carbon Dioxide

soot

Heat Trapped by Carbon Dioxide and Other Climate Pollutantsas of 2005

Source: IPCC-2007; Ramanathan and Xu, 2010

The other pollutants have almost the same warming effect as Carbon Dioxide

1975

One molecule of CFC has the same greenhouse effect as the addition of more than 10,000 molecules of Carbon Dioxide to the Atmosphere

How Long Have We known About the other Climate Pollutants?

Non-CO2 Gases contribute as much as CO2 to climate Change

When was the First International Assessment of the Other Pollutants?

What do we mean by Near-Term ?

With just carbon-dioxide mitigation, the warming is likelyto exceed 1.5 C to 2 C during the next 30 to 60 years

Ref: Ramanathan and Xu, 2010Raes and Seinfeld, 2009Mcracken, …..

CO2 reductions have to be complemented with Reductions in short-lived non-CO2 warming agents

1900 1950 2000 2050 2100280

310

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460

con

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(pp

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1900 1950 2000 2050 21000

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Even with 50% reductions by 2050, CO2 will Increase to 440 PPM; Commit More warming

Mitigation

Long-Term Near –Term

Build-up of Carbon Dioxide

Results from burning fossil fuels – essential to modern life

Remains in air for centuries

Main contributor to warming

Cutting down this emission is the permanent solution

Short-lived Gases & Dark Soot Particles

• 3 Gases - Methane, HFC [Hydro Fluorocarbons] and lower atmospheric ozone

• Pollutants last several days to few decades in air

• Current Warming effect - 80% of that of Carbon Dioxide

• Cutting down will buy time till permanent solution is in place

By Mitigating emissions of short-term climate pollutantsCan Delay large warming by few decades:

Ramanathan and Xu, 2010

Primary Mitigation Advantages ofNear-Term Climate Pollutants

• Easier to reduce. People can see immediate benefit

• Technology and regulatory systems are available

• Can be done locally and Nationally

Need proper incentives

Why the delays?– Poor Incentives -

cumbersome accounting systems in climate diplomacy

Some Visible Effects of Pollutants Ozone; Methane; Soot

• Regional: Melting of arctic snow and ice; Large warming of the

Himalayan-Tibetan Region ; Disrupting Monsoonal circulation

• Air pollution – unhealthy air

– Over 1.5 million deaths– annually

• Threat to Agriculture; Billions of dollars lost due to crop damages

» B

California Has Reduced its Black carbon ReductionsBy 50% from 1989 to 2008Bahadur , Feng, Russell, Ramanathan, 2010

1985 2010

UNEP’s ABC PROJECTUNEP’s ABC PROJECT

The first impact assessment report, Nov 2008

Preliminary Assessment Report, Aug 2002

Think Globally

Assess Regionally

UNEP integrated assessment of tropospheric ozone and black carbon (Preview)

Assessment Chair: Drew Shindell (NASA Goddard Institute for Space Studies, USA)

Assessment Vice Chairs: Frank Raes (EU Joint Research Centre, Ispra, Italy) V. Ramanathan (Scripps, Univ. of California, USA)Kim Oanh (Asian Institute of Technology (AIT), Thailand)Luis Cifuentes (Pontificia Universidad Católica ,Chile)

Assessment Scientific Secretariat: Johan Kuylenstierna, Kevin Hicks, SEI / Global

Atmospheric Pollution Forum

UNEP Coordinator: Volodymyr Demkine, UNEP DEWA

Coordinating Lead Authors: Emissions: David Streets; Atmospheric processes: David Fowler; Impacts: Lisa Emberson; Measures: Martin Williams

Modelling: Emissions - Markus Amann, IIASA (GAINS) GCMs: Drew Shindell et al – NASA GISS, Elisabetta Vignati et al - ECHAM and FASST Tool at JRCHealth: Susan Anenberg, US EPACrops: Rita van Dingenen – JRC Ispra

Economic Valuation – Nicholas Muller, Middlebury College

Group 1:

‘Methane Only’: Technical measures for methane

emissions1. Extended recovery of coal mine gas

2. Extended recovery and flaring (instead of venting) of associated gas from

production of crude oil and natural gas

3. Reduced gas leakage at compressor stations in long-distance gas transmission

pipelines

4. Separation and treatment of biodegradable municipal waste through recycling,

composting and anaerobic digestion

5. Upgrading primary wastewater treatment to secondary/tertiary treatment with gas

recovery and overflow control

6. Control of methane emissions from livestock, mainly through farm-scale anaerobic

digestion of manure from cattle and pigs with liquid manure management

7. Intermittent aeration of continuously flooded rice paddies

UNEP: Shindell et al, 2011

Group 2:

‘BC Tech’: Technical measures for black carbon 1. Replacing traditional coke ovens with modern recovery ovens,

including the improvement of end-of-pipe abatement measures (in developing countries)

2. Replacing traditional brick kilns with vertical shaft kilns and Hoffman kilns where

considered feasible (in developing countries)

3. Diesel particle filters for road vehicles and off-road mobile sources (excluding shipping)

4. Particle control at stationary engines

5. Improved stoves in developing countries in residential sector

Additional measures considered

[6. Wide-scale introduction of pellets stoves and boilers in the residential sector (in

industrialized countries)

[7. Use of coal briquettes in residential sector]

What about coal briquettes in China and BC emission control in E and N america – 16 measures – or

part of 3??? Also improved stoves????

UNEP: Shindell et al, 2011

Zaelke, 2009Ramanathan, 1975

We have mitigated Climate Change Already We can do it again